Clinical and cardiac magnetic resonance findings in post-COVID patients referred for suspected myocarditis.

OBJECTIVES: We assessed possible myocardial involvement in previously cardiac healthy post-COVID patients referred for persisting symptoms with suspected myocarditis. BACKGROUND: Prior studies suggested myocardial inflammation in patients with coronavirus-induced disease 2019 (COVID-19). However, the prevalence of cardiac involvement among COVID patients varied between 1.4 and 78%. METHODS: A total of 56 post-COVID patients without previous heart diseases were included consecutively into this study. All patients had positive antibody titers against SARS-CoV-2. Patients were referred for persistent symptoms such as chest pain/discomfort, shortness of breath, or intolerance to activity. All patients underwent standardized cardiac assessment including electrocardiogram (ECG), cardiac biomarkers, echocardiography, and cardiac magnetic resonance (CMR). RESULTS: 56 Patients (46 ± 12 years, 54% females) presented 71 ± 66 days after their COVID-19 disease. In most patients, the course of COVID-19 was mild, with hospital treatment being necessary in five (9%). At presentation, patients most often reported persistent fatigue (75%), chest pain (71%), and shortness of breath (66%). Acute myocarditis was confirmed by T1/T2-weighed CMR and elevated NTpro-BNP levels in a single patient (2%). Left ventricular ejection fraction was 56% in this patient. Additional eight patients (14%) showed suspicious CMR findings, including myocardial edema without fibrosis (n = 3), or non-ischemic myocardial injury suggesting previous inflammation (n = 5). However, myocarditis could ultimately not be confirmed according to 2018 Lake Louise criteria; ECG, echo and lab findings were inconspicuous in all eight patients. CONCLUSIONS: Among 56 post-COVID patients with persistent thoracic complaints final diagnosis of myocarditis could be confirmed in a single patient using CMR.

Coronary computed tomography angiography: a method coming of age.

In patients with stable symptoms suggestive of coronary artery disease (CAD), coronary CT angiography (CTA) allows for assessing several aspects of coronary atherosclerosis. Coronary artery stenoses are reliably detected, plaque formation can be quantified and characterized as calcified or non-calcified, and markers of potential instability such as expansive vascular remodeling, spotty calcification, and atheroma size can be described. As opposed to invasive coronary angiography, CTA visualizes the vessel lumen and wall. Being a purely anatomic test, even small plaques are detected with excellent sensitivity. At the other end of the spectrum, the hemodynamic significance of large plaque burden is sometimes overestimated. This may in part be corrected using mathematical modeling. Computational fluid dynamics of vascular anatomy and subtended myocardial mass provide for measures of CT-based fractional flow reserve (FFRCT). Large prospective trials have demonstrated the diagnostic utility of CTA in particular for ruling out obstructive CAD. The ability to detect non-obstructive plaque allows for improved risk prediction in comparison with functional testing, because even patients with sub-clinical atherosclerosis can be identified and selected for preventive medical treatment. This has led to incorporating CTA as one of several possible diagnostic tests for the evaluation of stable CAD in the actual European guidelines. Recently, it has even been forwarded as the first-line diagnostic test in the United Kingdom. The clinical implications of novel quantitative CTA-derived parameters such as FFRCT and non-calcified plaque volume are being examined in ongoing studies.

Coronary CT angiography in managing atherosclerosis.

Invasive coronary angiography (ICA) was the only method to image coronary arteries for a long time and is still the gold-standard. Technology of noninvasive imaging by coronary computed-tomography angiography (CCTA) has experienced remarkable progress during the last two decades. It is possible to visualize atherosclerotic lesions in the vessel wall in contrast to "lumenography" performed by ICA. Coronary artery disease can be ruled out by CCTA with excellent accuracy. The degree of stenoses is, however, often overestimated which impairs specificity. Atherosclerotic lesions can be characterized as calcified, non-calcified and partially calcified. Calcified plaques are usually quantified using the Agatston-Score. Higher scores are correlated with worse cardiovascular outcome and increased risk of cardiac events. For non-calcified or partially calcified plaques different angiographic findings like positive remodelling, a large necrotic core or spotty calcification more frequently lead to myocardial infarctions. CCTA is an important tool with increasing clinical value for ruling out coronary artery disease or relevant stenoses as well as for advanced risk stratification.

The adverse events and hemodynamic effects of adenosine-based cardiac MRI.

OBJECTIVE: We wanted to prospectively assess the adverse events and hemodynamic effects associated with an intravenous adenosine infusion in patients with suspected or known coronary artery disease and who were undergoing cardiac MRI. MATERIALS AND METHODS: One hundred and sixty-eight patients (64 ± 9 years) received adenosine (140 µg/kg/min) during cardiac MRI. Before and during the administration, the heart rate, systemic blood pressure, and oxygen saturation were monitored using a MRI-compatible system. We documented any signs and symptoms of potential adverse events. RESULTS: In total, 47 out of 168 patients (28%) experienced adverse effects, which were mostly mild or moderate. In 13 patients (8%), the adenosine infusion was discontinued due to intolerable dyspnea or chest pain. No high grade atrioventricular block, bronchospasm or other life-threatening adverse events occurred. The hemodynamic measurements showed a significant increase in the heart rate during adenosine infusion (69.3 ± 11.7 versus 82.4 ± 13.0 beats/min, respectively; p < 0.001). A significant but clinically irrelevant increase in oxygen saturation occurred during adenosine infusion (96 ± 1.9% versus 97 ± 1.3%, respectively; p < 0.001). The blood pressure did not significantly change during adenosine infusion (systolic: 142.8 ± 24.0 versus 140.9 ± 25.7 mmHg; diastolic: 80.2 ± 12.5 mmHg versus 78.9 ± 15.6, respectively). CONCLUSION: This study confirms the safety of adenosine infusion during cardiac MRI. A considerable proportion of all patients will experience minor adverse effects and some patients will not tolerate adenosine infusion. However, all adverse events can be successfully managed by a radiologist. The increased heart rate during adenosine infusion highlights the need to individually adjust the settings according to the patient, e.g., the number of slices of myocardial perfusion imaging.

Comparison of prognostic usefulness (three years) of computed tomographic angiography versus 64-slice computed tomographic calcium scanner in subjects without significant coronary artery disease.

Coronary computerized tomographic angiography (CTA) has been used as a noninvasive method for ruling out high-grade stenoses. Even in the absence of such stenoses, analysis of coronary atherosclerosis may provide for important prognostic information, and this may be superior to exclusive coronary artery calcium scoring. We tested this hypothesis in patients undergoing CTA for clinical indications who had no stenoses requiring revascularization. From December 2004 to December 2006, 706 consecutive patients who underwent CTA but had no high-grade stenoses were included (58% men, mean age 59 ± 11 years). CTA and coronary artery calcium scoring (Agatston method) were performed using a 64-slice CT scanner with a gantry rotation time of 330 ms. CT angiograms were categorized as completely normal (group 1), showing minor plaque (group 2), or showing intermediate stenoses (group 3). Follow-up information was obtained in 670 patients (95%) over a mean of 3.2 years. There were 31 major adverse events (5%), namely 9 deaths (all noncoronary), 2 myocardial infarctions, 5 strokes, 13 coronary revascularization procedures (percutaneous or surgical > 6 months after CTA), and 2 peripheral percutaneous interventions. Coronary status as defined by CTA was predictive of major events after adjustment for age and gender. In group 1, the probability of event-free survival at 3 years was 100%; in group 2, it was 96%; and in group 3, it was 91%. Compared to group 1, the risk in group 2 was increased 2.3-fold, and in group 3, it was increased 5.6-fold after adjusting for age and gender. However, after addition of the coronary artery calcium score to the regression analysis, CT angiographic status no longer appeared to be predictive. In conclusion, the risk of a major adverse cardiovascular event or death increased in a graded manner with degree of coronary atherosclerosis as defined by CTA even in the absence of high-grade coronary stenoses. However, in the absence of high-grade stenoses, we were unable to demonstrate a superior prognostic value of CTA compared to coronary artery calcium.

The role of CT angiography in risk stratification for atherosclerosis.

Multislice CT coronary angiography (CTA) offers the opportunity to visualize the coronary arteries in a complete fashion, including the arterial wall, vessel dimensions and tortuosity, and calcified and noncalcified plaques. The ability of CTA to reliably rule out high-grade stenoses in patients with an intermediate likelihood of coronary artery disease has been well established. Recently, CTA applications have been extended to interrogate coronary plaques in more detail. In patients with acute coronary syndrome, culprit plaques were observed to have a larger volume, less solid but spottier calcification, and an increased tendency for expansive (positive) remodeling. A number of prospective studies have suggested that the quantification of overall coronary atherosclerosis adds incremental prognostic power in addition to conventional risk factor analysis. With novel scanning algorithms promising a substantial radiation dose reduction, risk stratification for coronary atherosclerosis by using CTA may become an option in selected patients. It is still undetermined if this method offers a prognostic benefit over conventional methods and how it compares to calcium scoring. The currently available data are encouraging.

Left circumflex coronary artery fistula to the superior vena cava: assessment of the exact anatomy by multidetector CT.

A 62-year-old woman with mild dyspnea on exertion underwent coronary angiography. A large fistula of the left circumflex artery was found but the exit site of this unusual anomaly could not be established. Contrast-enhanced multidetector computed tomography of the coronary arteries was performed which allowed clear identification of the drainage of the fistula into the superior vena cava.

Thrombus detection in the left atrial appendage using contrast-enhanced MRI: a pilot study.

OBJECTIVE: Left atrial thrombi are an important cause for embolism-related morbidity and mortality. Transesophageal echocardiography (TEE), the clinical reference, is semiinvasive; thus, we aimed to assess the value of contrast-enhanced cardiovascular MRI for the detection of thrombus in the left atrial appendage. CONCLUSION: The image quality was good for both 2D perfusion (grade 4 +/- 1) and 3D turbo fast low-angle shot (FLASH) (grade 4 +/- 1, n.s.). Compared with TEE, 2D perfusion, 3D turboFLASH, and the combination of both techniques yielded sensitivities of 47/35/44%, specificities of 50/67/67%, positive predictive values of 73/75/80%, and negative predictive values of 25/27/29%, respectively. The size of the thrombus was overestimated by 2D perfusion (66%) and by 3D turboFLASH (25%) and agreement for location and shape of thrombus was 50% and 75% for 2D perfusion and 75% and 50% for 3D turboFLASH, respectively. The TEE thrombus size was significantly larger in patients with true-positive diagnoses by 2D perfusion (148%) and by 3D turboFLASH (151%) when compared with patients with false-negative diagnoses (p < 0.05 for both). No such difference was found for image quality, time delay between TEE and MRI examination, and location and shape of thrombi. Contrast-enhanced MRI lacks diagnostic accuracy for the detection of thrombi in the left atrial appendage. Future technical improvements are essential to establish this technique as a noninvasive alternative to TEE.